1. Field of the Invention
The present invention generally relates to data communication networks and, more particularly, to systems and methods for determining the probable network path or paths between two nodes in a network topology.
2. Description of the Related Art
A data communications network generally includes a group of devices, such as computers, repeaters, bridges, switches, routers, etc., situated at network nodes and a collection of communication channels for interconnecting the various nodes. Hardware and software associated with the network and, particularly, the devices permit the devices to exchange data electronically via the communication channels.
The size of networks varies. A local area network (LAN) is a network of devices in close proximity, typically less then one mile, and usually connected by a single cable, for instance, a coaxial cable. A wide area network (WAN) is a network of devices which are separated by longer distances, often connected by, for example, telephone lines or satellite links. In fact, some WANs span the U.S. as well as the world. Furthermore, many of these networks are widely available for use by the public, including universities and commercial industries.
A very popular industry standard protocol for data communication along the networks is the Internet Protocol (IP). In time, the Transmission Control Protocol (TCP) and the Unreliable Datagram Protocol (UDP) were developed for use with the IP. The former protocol (TCP/IP) is a protocol which guarantees transfer of data without errors, as it implements certain check functionality, and the latter protocol (UDP/IP) is a protocol which does not guarantee transfer of data, but requires must much less overhead than the TCP/IP platform. Furthermore, in order to keep track of and manage the various devices situated on a network, the simple network management protocol (SNMP) was eventually developed for use with the UDP/IP platform. The use of the foregoing protocols has become extensive in the industry, and numerous venders manufacture many types of networks devices which can employ these protocols.
Many management software packages (“management platforms”) are presently available for implementing “management stations” on a network and particularly in connection with the SNMP. Examples of commercially available SNMP management software packages include OpenView from the Hewlett-Packard Company, NetView/6000 from IBM Corp., Spectrum from Cabletron Systems, Inc., Netlabs/Manager from Netlabs, Inc., and SunNet Manager from Sun Connect, Inc. The nodes on a network and their interconnections, oftentimes referred to as a network “topology,” are best displayed in a graphical format and most, if not all, of the available management packages provide for this feature. Typically, with these packages, a network can be viewed from different vantage points, depending on the scope of the view desired. For example, one view of the network could be a very wide encompassing view of all nodes on the entire network. A second view could be a view of those portions of a network within a local range, for example, within a particular site or building. A third view of a network, often called a segment, could be a view of the nodes attached to a particular LAN cable.
Hewlett-Packard's very successful OpenView has been the subject of several patents, including, for instance, U.S. Pat. No. 5,185,860, issued to J. C. Wu on Feb. 9, 1993, and U.S. Pat. No. 5,276,789, issued to Besaw et al. on Jan. 4, 1994, the disclosures of which are incorporated herein by reference. U.S. Pat. No. 5,185,860 describes an automatic discovery system for a management station for determining the network devices and interconnections of a network, or the topology. U.S. Pat. No. 5,276,789 describes a graphic display system for a management station for graphically displaying the topology of a network and provides for various views, including, Internet, segment, and node views, that can be requested by a user.
When utilizing a management station, such as a station implemented by Hewlett-Packard's OpenView, a user may consider it beneficial to be able to predict the probable path or paths between two nodes in a network. However, heretofore, the ability to determine the probable path or paths between two nodes has not been addressed by available management platforms.
Therefore there is a need for improved systems and methods which address these and other shortcomings of the prior art.